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  <script>
    function arr(nums) {
      let res = -1;
      for (let i = 0; i < nums.length - 1; i++) {
        for (let j = i + 1; j < nums.length; j++) {
          if (nums[i] === -nums[j]) {
            res = Math.max(Math.abs(nums[i]), res);
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      return res;
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    console.log(arr([-1, 2, -3, 3]));
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